time to change the noisy steering pump

hi guys still having trouble with the power steering car is running superb on veg oil but the steering pump is now making a terrible noise . i used to get the yellow warninh light on the dash but i used to turn the engine off then back on and it would be gone . then i checked the power steering fluid that was a mission on its own with a bit off skin off each knuckle but bottle was full . so its been great untill 2 weeks ago it started making a few whineing noises but gradually getting worse . it now sounds like i got a cat stuck under the wheel arch so its time to change something but what i dont know would it be the pump cheers lads